Apple has acknowledged that a small percentage of the hard drives used in MacBooks bought between May 2006 and December 2007 are defective. Unfortunately for users, this defect manifests itself in a hard drive failure: the affected laptops simply stop working and display a question mark on a file icon when they are turned on.

Luckily for these affected users, Apple has announced that they are eligible for a free replacement under a warranty extension. Apple is encouraging users with this frustrating problem to go to an Apple store or contact customer support for a replacement. Those who have already paid for repairs may be eligible for a refund.

Unfortunately, a hard drive replacement won’t bring back lost data (so please, please make sure you are backing up to an external hard drive or some other form of reliable backup). The new warranty extension extends either three years from purchase date or to August 15, 2010, whichever is longer.